cmd/ypcmd/ypserv_proc.c

/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License, Version 1.0 only
 * (the "License").  You may not use this file except in compliance
 * with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright 2003 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/*  Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T */
/*    All Rights Reserved   */

/*
 * Portions of this source code were derived from Berkeley 4.3 BSD
 * under license from the Regents of the University of California.
 */

#pragma ident   "%Z%%M% %I% %E% SMI"

/*
 *
 * This contains YP server code which supplies the set of functions
 * requested using rpc.   The top level functions in this module
 * are those which have symbols of the form YPPROC_xxxx defined in
 * yp_prot.h, and symbols of the form YPOLDPROC_xxxx defined in ypsym.h.
 * The latter exist to provide compatibility to the old version of the yp
 * protocol/server, and may emulate the behavior of the previous software
 * by invoking some other program.
 *
 * This module also contains functions which are used by (and only by) the
 * top-level functions here.
 */

#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <dirent.h>
#include <limits.h>
#include <sys/systeminfo.h>
#include <rpc/rpc.h>
#include <string.h>
#include <malloc.h>
#include <stdlib.h>
#include <unistd.h>
#include <stdio.h>
#include "ypsym.h"
#include "ypdefs.h"
#include <ctype.h>

/* Use shim version of DBM calls */
#include "shim.h"
#include "shim_hooks.h"

USE_YP_PREFIX
USE_YP_SECURE
USE_YP_INTERDOMAIN

#ifndef YPXFR_PROC
#define YPXFR_PROC "/usr/lib/netsvc/yp/ypxfr"
#endif
static char ypxfr_proc[] = YPXFR_PROC;
#ifndef YPPUSH_PROC
#define YPPUSH_PROC "/usr/lib/netsvc/yp/yppush"
#endif
static char yppush_proc[] = YPPUSH_PROC;
struct yppriv_sym {
    char *sym;
    unsigned len;
};
static  char err_fork[] = "ypserv:  %s fork failure.\n";
#define FORK_ERR logprintf(err_fork, fun)
static char err_execl[] = "ypserv:  %s execl failure.\n";
#define EXEC_ERR logprintf(err_execl, fun)
static char err_respond[] = "ypserv: %s can't respond to rpc request.\n";
#define RESPOND_ERR logprintf(err_respond, fun)
static char err_free[] = "ypserv: %s can't free args.\n";
#define FREE_ERR logprintf(err_free, fun)
static char err_map[] = "ypserv: %s no such map or access denied.\n";
#define MAP_ERR logprintf(err_map, fun)
static char err_vers[] = "ypserv: %s version not supported.\n";
#define VERS_ERR logprintf(err_vers, fun)

static void ypfilter(DBM *fdb, datum *inkey, datum *outkey, datum *val,
            uint_t *status, bool_t update);
static bool isypsym(datum *key);
static bool xdrypserv_ypall(XDR *xdrs, struct ypreq_nokey *req);
static int multihomed(struct ypreq_key req, struct ypresp_val *resp,
            SVCXPRT *xprt, DBM *fdb);
static int omultihomed(struct yprequest req, struct ypresponse *resp,
            SVCXPRT *xprt, DBM *fdb);


/* For DNS forwarding */
extern bool dnsforward;
extern bool client_setup_failure;
extern int resolv_pid;
extern CLIENT *resolv_client;
extern char *resolv_tp;

/*
 * This determines whether or not a passed domain is served by this
 * server, and returns a boolean.  Used by both old and new protocol
 * versions.
 */
void
ypdomain(SVCXPRT *transp, bool always_respond)
{
    char domain_name[YPMAXDOMAIN + 1];
    char *pdomain_name = domain_name;
    bool isserved;
    char *fun = "ypdomain";
    struct netbuf *nbuf;
    sa_family_t af;

    memset(domain_name, 0, sizeof (domain_name));

    if (!svc_getargs(transp, (xdrproc_t)xdr_ypdomain_wrap_string,
                (caddr_t)&pdomain_name)) {
        svcerr_decode(transp);
        return;
    }

    /*
     * If the file /var/yp/securenets is present on the server, and if
     * the hostname is present in the file, then let the client bind to
     * the server.
     */
    nbuf = svc_getrpccaller(transp);
    af = ((struct sockaddr_storage *)nbuf->buf)->ss_family;
    if (af != AF_INET && af != AF_INET6) {
        logprintf("Protocol incorrect\n");
        return;
    }

    if (!(check_secure_net_ti(nbuf, fun))) {
        MAP_ERR;
        return;
    }

    isserved = ypcheck_domain(domain_name);

    if (isserved || always_respond) {

        if (!svc_sendreply(transp, xdr_bool, (char *)&isserved)) {
            RESPOND_ERR;
        }
        if (!isserved)
            logprintf("Domain %s not supported\n",
                    domain_name);

    } else {
        /*
         * This case is the one in which the domain is not
         * supported, and in which we are not to respond in the
         * unsupported case.  We are going to make an error happen
         * to allow the portmapper to end his wait without the
         * normal timeout period.  The assumption here is that
         * the only process in the world which is using the function
         * in its no-answer-if-nack form is the portmapper, which is
         * doing the krock for pseudo-broadcast.  If some poor fool
         * calls this function as a single-cast message, the nack
         * case will look like an incomprehensible error.  Sigh...
         * (The traditional Unix disclaimer)
         */

        svcerr_decode(transp);
        logprintf("Domain %s not supported (broadcast)\n",
                domain_name);
    }
}

/*
 * This implements the yp "match" function.
 */
void
ypmatch(SVCXPRT *transp, struct svc_req *rqstp)
{
    struct ypreq_key req;
    struct ypresp_val resp;
    char *fun = "ypmatch";
    DBM *fdb;

    memset(&req, 0, sizeof (req));
    memset(&resp, 0, sizeof (resp));
    resp.status = (unsigned)YP_NOKEY;

    if (!svc_getargs(transp, (xdrproc_t)xdr_ypreq_key, (char *)&req)) {
        svcerr_decode(transp);
        return;
    }

    /*
     * sanity check the map name and to a DBM lookup
     * also perform an access check...
     */
    if ((fdb = ypset_current_map(req.map, req.domain,
                    &resp.status)) != NULL &&
        yp_map_access(transp, &resp.status, fdb)) {

        /* Check with the DBM database */
        resp.valdat = dbm_fetch(fdb, req.keydat);
        if (resp.valdat.dptr != NULL) {
            resp.status = YP_TRUE;
            if (!silent)
                printf("%s: dbm: %40.40s\n",
                    fun, resp.valdat.dptr);
            goto send_reply;
        }

        /*
         * If we're being asked to match YP_SECURE or YP_INTERDOMAIN
         * and we haven't found it in the dbm file, then we don't
         * really want to waste any more time.  Specifically, we don't
         * want to ask DNS
         */
        if (req.keydat.dsize == 0 ||
            req.keydat.dptr == NULL ||
            req.keydat.dptr[0] == '\0' ||
    strncmp(req.keydat.dptr, yp_secure, req.keydat.dsize) == 0 ||
    strncmp(req.keydat.dptr, yp_interdomain, req.keydat.dsize) == 0) {
            goto send_reply;
        }

        /* Let's try the YP_MULTI_ hack... */
#ifdef MINUS_C_OPTION
        if (multiflag == TRUE && multihomed(req, &resp, transp, fdb))
            goto send_reply;
#else
        if (multihomed(req, &resp, transp, fdb))
            goto send_reply;
#endif

        /*
         * Let's try DNS, but if client_setup_failure is set,
         * we have tried DNS in the past and failed, there is
         * no reason in forcing an infinite loop by turning
         * off DNS in setup_resolv() only to turn it back on
         * again here.
         */
        if (!dnsforward && !client_setup_failure) {
            datum idkey, idval;
            idkey.dptr = yp_interdomain;
            idkey.dsize = yp_interdomain_sz;
            idval = dbm_fetch(fdb, idkey);
            if (idval.dptr)
                dnsforward = TRUE;
        }

        if (dnsforward) {
            if (!resolv_pid || !resolv_client) {
                setup_resolv(&dnsforward, &resolv_pid,
                        &resolv_client, resolv_tp, 0);
                if (resolv_client == NULL)
                    client_setup_failure = TRUE;
            }

            if (resolv_req(&dnsforward, &resolv_client,
                        &resolv_pid, resolv_tp,
                        rqstp->rq_xprt, &req,
                        req.map) == TRUE)
                goto free_args;
        }
    }
    send_reply:

    if (!svc_sendreply(transp, (xdrproc_t)xdr_ypresp_val,
                (caddr_t)&resp)) {
        RESPOND_ERR;
    }

    free_args:

    if (!svc_freeargs(transp, (xdrproc_t)xdr_ypreq_key,
                (char *)&req)) {
        FREE_ERR;
    }
}


/*
 * This implements the yp "get first" function.
 */
void
ypfirst(SVCXPRT *transp)
{
    struct ypreq_nokey req;
    struct ypresp_key_val resp;
    char *fun = "ypfirst";
    DBM *fdb;

    memset(&req, 0, sizeof (req));
    memset(&resp, 0, sizeof (resp));

    if (!svc_getargs(transp,
                (xdrproc_t)xdr_ypreq_nokey,
                (char *)&req)) {
        svcerr_decode(transp);
        return;
    }

    if ((fdb = ypset_current_map(req.map, req.domain,
                    &resp.status)) != NULL &&
        yp_map_access(transp, &resp.status, fdb)) {
        ypfilter(fdb, NULL,
            &resp.keydat, &resp.valdat, &resp.status, FALSE);
    }

    if (!svc_sendreply(transp,
                (xdrproc_t)xdr_ypresp_key_val,
                (char *)&resp)) {
        RESPOND_ERR;
    }

    if (!svc_freeargs(transp, (xdrproc_t)xdr_ypreq_nokey,
                (char *)&req)) {
        FREE_ERR;
    }
}

/*
 * This implements the yp "get next" function.
 */
void
ypnext(SVCXPRT *transp)
{
    struct ypreq_key req;
    struct ypresp_key_val resp;
    char *fun = "ypnext";
    DBM *fdb;

    memset(&req, 0, sizeof (req));
    memset(&resp, 0, sizeof (resp));

    if (!svc_getargs(transp, (xdrproc_t)xdr_ypreq_key, (char *)&req)) {
        svcerr_decode(transp);
        return;
    }

    if ((fdb = ypset_current_map(req.map, req.domain,
                    &resp.status)) != NULL &&
        yp_map_access(transp, &resp.status, fdb)) {
        ypfilter(fdb, &req.keydat,
            &resp.keydat, &resp.valdat, &resp.status, FALSE);
    }

    if (!svc_sendreply(transp,
                (xdrproc_t)xdr_ypresp_key_val,
                (char *)&resp)) {
        RESPOND_ERR;
    }

    if (!svc_freeargs(transp,
                (xdrproc_t)xdr_ypreq_key,
                (char *)&req)) {
        FREE_ERR;
    }
}

/*
 * This implements the "transfer map" function.  It takes the domain
 * and map names and the callback information provided by the
 * requester (yppush on some node), and execs a ypxfr process to do
 * the actual transfer.
 */
void
ypxfr(SVCXPRT *transp, int prog)
{
    struct ypreq_newxfr newreq;
    struct ypreq_xfr oldreq;
    struct ypresp_val resp;  /* not returned to the caller */
    char transid[32];
    char proto[32];
    char name[256];
    char *pdomain, *pmap;
    pid_t pid = -1;
    char *fun = "ypxfr";
    DBM *fdb;

    if (prog == YPPROC_NEWXFR) {
        memset(&newreq, 0, sizeof (newreq));
        if (!svc_getargs(transp, (xdrproc_t)xdr_ypreq_newxfr,
                (char *)&newreq)) {
            svcerr_decode(transp);
            return;
        }

#ifdef OPCOM_DEBUG
        fprintf(stderr, "newreq:\n"
            "\tmap_parms:\n"
            "\t\tdomain:    %s\n"
            "\t\tmap:       %s\n"
            "\t\tordernum:  %u\n"
            "\t\towner:     %s\n"
            "\ttransid:    %u\n"
            "\tproto:      %u\n"
            "\tname:       %s\n\n",
            newreq.map_parms.domain,
            newreq.map_parms.map,
            newreq.map_parms.ordernum,
            newreq.map_parms.owner,
            newreq.transid,
            newreq.proto,
            newreq.name);
#endif
        sprintf(transid, "%u", newreq.transid);
        sprintf(proto, "%u", newreq.proto);
        sprintf(name, "%s", newreq.ypxfr_owner);
        pdomain = newreq.ypxfr_domain;
        pmap = newreq.ypxfr_map;
    } else if (prog == YPPROC_XFR) {
        memset(&oldreq, 0, sizeof (oldreq));
        if (!svc_getargs(transp,
                    (xdrproc_t)xdr_ypreq_xfr,
                    (char *)&oldreq)) {
            svcerr_decode(transp);
            return;
        }

#ifdef OPCOM_DEBUG
        fprintf(stderr, "oldreq:\n"
            "\tmap_parms:\n"
            "\t\tdomain:    %s\n"
            "\t\tmap:       %s\n"
            "\t\tordernum:  %u\n"
            "\t\towner:     %s\n"
            "\ttransid:    %u\n"
            "\tproto:      %u\n"
            "\tport:       %u\n\n",
            oldreq.map_parms.domain,
            oldreq.map_parms.map,
            oldreq.map_parms.ordernum,
            oldreq.map_parms.owner,
            oldreq.transid,
            oldreq.proto,
            oldreq.port);
#endif

        sprintf(transid, "%u", oldreq.transid);
        sprintf(proto, "%u", oldreq.proto);
        sprintf(name, "%s", oldreq.ypxfr_owner);
        pdomain = oldreq.ypxfr_domain;
        pmap = oldreq.ypxfr_map;
    } else {
        VERS_ERR;
    }

    /* Check that the map exists and is accessible */
    if ((fdb = ypset_current_map(pmap, pdomain, &resp.status)) != NULL &&
        yp_map_access(transp, &resp.status, fdb)) {

        pid = vfork();
        if (pid == -1) {
            FORK_ERR;
        } else if (pid == 0) {
            if (prog == YPPROC_NEWXFR || prog == YPPROC_XFR) {
#ifdef OPCOM_DEBUG
            fprintf(stderr,
                "EXECL: %s, -d, %s, -C, %s, %s, %s, %s\n",
                ypxfr_proc, pdomain,
                transid, proto, name, pmap);
#endif
            if (execl(ypxfr_proc, "ypxfr", "-d",
                    pdomain, "-C", transid, proto,
                    name, pmap, NULL))
                EXEC_ERR;
            } else {
            VERS_ERR;
            }
            _exit(1);
        }

    } else {
        MAP_ERR;
    }
    if (!svc_sendreply(transp, xdr_void, 0)) {
        RESPOND_ERR;
    }

    if (prog == YPPROC_NEWXFR) {
        if (!svc_freeargs(transp,
                    (xdrproc_t)xdr_ypreq_newxfr,
                    (char *)&newreq)) {
            FREE_ERR;
        }
    }
}

/*
 * This implements the "get all" function.
 */
void
ypall(SVCXPRT *transp)
{
    struct ypreq_nokey req;
    struct ypresp_val resp;  /* not returned to the caller */
    pid_t pid;
    char *fun = "ypall";
    DBM *fdb;

    req.domain = req.map = NULL;

    memset((char *)&req, 0, sizeof (req));

    if (!svc_getargs(transp,
                (xdrproc_t)xdr_ypreq_nokey,
                (char *)&req)) {
        svcerr_decode(transp);
        return;
    }

    pid = fork1();

    if (pid) {

        if (pid == -1) {
            FORK_ERR;
        }

        if (!svc_freeargs(transp,
                    (xdrproc_t)xdr_ypreq_nokey,
                    (char *)&req)) {
            FREE_ERR;
        }

        return;
    }

    /*
     * access control hack:  If denied then invalidate the map name.
     */
    ypclr_current_map();
    if ((fdb = ypset_current_map(req.map,
        req.domain, &resp.status)) != NULL &&
        !yp_map_access(transp, &resp.status, fdb)) {

        req.map[0] = '-';
    }

    /*
     * This is the child process.  The work gets done by xdrypserv_ypall/
     * we must clear the "current map" first so that we do not
     * share a seek pointer with the parent server.
     */

    if (!svc_sendreply(transp,
                (xdrproc_t)xdrypserv_ypall,
                (char *)&req)) {
        RESPOND_ERR;
    }

    if (!svc_freeargs(transp,
                (xdrproc_t)xdr_ypreq_nokey,
                (char *)&req)) {
        FREE_ERR;
    }

    /*
     * In yptol mode we may start a cache update thread within a child
     * process. It is thus important that child processes do not exit,
     * killing any such threads, before the thread has completed.
     */
    if (yptol_mode) {
        thr_join(0, NULL, NULL);
    }

    exit(0);
}

/*
 * This implements the "get master name" function.
 */
void
ypmaster(SVCXPRT *transp)
{
    struct ypreq_nokey req;
    struct ypresp_master resp;
    char *nullstring = "";
    char *fun = "ypmaster";
    DBM *fdb;

    memset((char *)&req, 0, sizeof (req));
    resp.master = nullstring;
    resp.status = YP_TRUE;

    if (!svc_getargs(transp,
                (xdrproc_t)xdr_ypreq_nokey,
                (char *)&req)) {
        svcerr_decode(transp);
        return;
    }

    if ((fdb = ypset_current_map(req.map,
        req.domain, &resp.status)) != NULL &&
        yp_map_access(transp, &resp.status, fdb)) {

        if (!ypget_map_master(&resp.master, fdb)) {
            resp.status = (unsigned)YP_BADDB;
        }
    }

    if (!svc_sendreply(transp,
                (xdrproc_t)xdr_ypresp_master,
                (char *)&resp)) {
        RESPOND_ERR;
    }

    if (!svc_freeargs(transp,
                (xdrproc_t)xdr_ypreq_nokey,
                (char *)&req)) {
        FREE_ERR;
    }
}

/*
 * This implements the "get order number" function.
 */
void
yporder(SVCXPRT *transp)
{
    struct ypreq_nokey req;
    struct ypresp_order resp;
    char *fun = "yporder";
    DBM *fdb;

    req.domain = req.map = NULL;
    resp.status  = YP_TRUE;
    resp.ordernum  = 0;

    memset((char *)&req, 0, sizeof (req));

    if (!svc_getargs(transp,
                (xdrproc_t)xdr_ypreq_nokey,
                (char *)&req)) {
        svcerr_decode(transp);
        return;
    }

    resp.ordernum = 0;

    if ((fdb = ypset_current_map(req.map,
                    req.domain,
                    &resp.status)) != NULL &&
        yp_map_access(transp, &resp.status, fdb)) {

        if (!ypget_map_order(req.map, req.domain, &resp.ordernum)) {
            resp.status = (unsigned)YP_BADDB;
        }
    }

    if (!svc_sendreply(transp,
                (xdrproc_t)xdr_ypresp_order,
                (char *)&resp)) {
        RESPOND_ERR;
    }

    if (!svc_freeargs(transp,
                (xdrproc_t)xdr_ypreq_nokey,
                (char *)&req)) {
        FREE_ERR;
    }
}

void
ypmaplist(SVCXPRT *transp)
{
    char domain_name[YPMAXDOMAIN + 1];
    char *pdomain = domain_name;
    char *fun = "ypmaplist";
    struct ypresp_maplist maplist;
    struct ypmaplist *tmp;

    maplist.list = (struct ypmaplist *)NULL;

    memset(domain_name, 0, sizeof (domain_name));

    if (!svc_getargs(transp,
                (xdrproc_t)xdr_ypdomain_wrap_string,
                (caddr_t)&pdomain)) {
        svcerr_decode(transp);
        return;
    }

    maplist.status = yplist_maps(domain_name, &maplist.list);

    if (!svc_sendreply(transp,
                (xdrproc_t)xdr_ypresp_maplist,
                (char *)&maplist)) {
        RESPOND_ERR;
    }

    while (maplist.list) {
        tmp = maplist.list->ypml_next;
        free((char *)maplist.list);
        maplist.list = tmp;
    }
}

/*
 * Ancillary functions used by the top-level functions within this
 * module
 */

/*
 * This returns TRUE if a given key is a yp-private symbol, otherwise
 * FALSE
 */
static bool
isypsym(datum *key)
{
    if ((key->dptr == NULL) ||
        (key->dsize < yp_prefix_sz) ||
        memcmp(yp_prefix, key->dptr, yp_prefix_sz) ||
        (!memcmp(key->dptr, "YP_MULTI_", 9))) {
        return (FALSE);
    }
    return (TRUE);
}

/*
 * This provides private-symbol filtration for the enumeration functions.
 */
static void
ypfilter(DBM *fdb, datum *inkey, datum *outkey, datum *val, uint_t *status,
                            bool_t update)
{
    datum k;

    if (inkey) {

        if (isypsym(inkey)) {
            *status = (unsigned)YP_BADARGS;
            return;
        }

        k = dbm_do_nextkey(fdb, *inkey);
    } else {
        k = dbm_firstkey(fdb);
    }

    while (k.dptr && isypsym(&k)) {
        k = dbm_nextkey(fdb);
    }

    if (k.dptr == NULL) {
        *status = YP_NOMORE;
        return;
    }

    *outkey = k;

    /*
     * In N2L mode we must call a version of dbm_fetch() that either does
     * or does not check for entry updates. In non N2L mode both of these
     * will end up doing a normal dbm_fetch().
     */
    if (update)
        *val = shim_dbm_fetch(fdb, k);
    else
        *val = shim_dbm_fetch_noupdate(fdb, k);

    if (val->dptr != NULL) {
        *status = YP_TRUE;
    } else {
        *status = (unsigned)YP_BADDB;
    }
}

/*
 * Serializes a stream of struct ypresp_key_val's.  This is used
 * only by the ypserv side of the transaction.
 */
static bool
xdrypserv_ypall(XDR *xdrs, struct ypreq_nokey *req)
{
    bool_t more = TRUE;
    struct ypresp_key_val resp;
    DBM *fdb;

    resp.keydat.dptr = resp.valdat.dptr = (char *)NULL;
    resp.keydat.dsize = resp.valdat.dsize = 0;

    if ((fdb = ypset_current_map(req->map, req->domain,
                    &resp.status)) != NULL) {
        ypfilter(fdb, (datum *) NULL, &resp.keydat, &resp.valdat,
                &resp.status, FALSE);

        while (resp.status == YP_TRUE) {
            if (!xdr_bool(xdrs, &more)) {
                return (FALSE);
            }

            if (!xdr_ypresp_key_val(xdrs, &resp)) {
                return (FALSE);
            }

            ypfilter(fdb, &resp.keydat, &resp.keydat, &resp.valdat,
                    &resp.status, FALSE);
        }
    }

    if (!xdr_bool(xdrs, &more)) {
        return (FALSE);
    }

    if (!xdr_ypresp_key_val(xdrs, &resp)) {
        return (FALSE);
    }

    more = FALSE;

    if (!xdr_bool(xdrs, &more)) {
        return (FALSE);
    }

    return (TRUE);
}

/*
 * Additions for sparc cluster support
 */

/*
 * Check for special multihomed host cookie in the key.  If there,
 * collect the addresses from the comma separated list and return
 * the one that's nearest the client.
 */
static int
multihomed(struct ypreq_key req, struct ypresp_val *resp,
        SVCXPRT *xprt, DBM *fdb)
{
    char *cp, *bp;
    ulong_t bestaddr, call_addr;
    struct netbuf *nbuf;
    char name[PATH_MAX];
    static char localbuf[_PBLKSIZ]; /* buffer for multihomed IPv6 addr */

    if (strcmp(req.map, "hosts.byname") &&
            strcmp(req.map, "ipnodes.byname"))
        /* default status is YP_NOKEY */
        return (0);

    if (strncmp(req.keydat.dptr, "YP_MULTI_", 9)) {
        datum tmpname;

        strncpy(name, "YP_MULTI_", 9);
        strncpy(name + 9, req.keydat.dptr, req.keydat.dsize);
        tmpname.dsize = req.keydat.dsize + 9;
        tmpname.dptr = name;
        resp->valdat = dbm_fetch(fdb, tmpname);
    } else {
        /*
         * Return whole line (for debugging) if YP_MULTI_hostnam
         * is specified.
         */
        resp->valdat = dbm_fetch(fdb, req.keydat);
        if (resp->valdat.dptr != NULL)
            return (1);
    }

    if (resp->valdat.dptr == NULL)
        return (0);

    strncpy(name, req.keydat.dptr, req.keydat.dsize);
    name[req.keydat.dsize] = NULL;

    if (strcmp(req.map, "ipnodes.byname") == 0) {
        /*
         * This section handles multihomed IPv6 addresses.
         * It returns all the IPv6 addresses one per line and only
         * the requested hostname is returned.  NO aliases will be
         * returned.  This is done exactly the same way DNS forwarding
         * daemon handles multihomed hosts.
         * New IPv6 enabled clients should be able to handle this
         * information returned.  The sorting is also the client's
         * responsibility.
         */

        char *buf, *endbuf;

        if ((buf = strdup(resp->valdat.dptr)) == NULL) /* no memory */
            return (0);
        if ((bp = strtok(buf, " \t")) == NULL) { /* no address field */
            free(buf);
            return (0);
        }
        if ((cp = strtok(NULL, "")) == NULL) { /* no host field */
            free(buf);
            return (0);
        }
        if ((cp = strtok(bp, ",")) != NULL) { /* multihomed host */
            int bsize;

            localbuf[0] = '\0';
            bsize = sizeof (localbuf);
            endbuf = localbuf;

            while (cp) {
                if ((strlen(cp) + strlen(name)) >= bsize) {
                    /* out of range */
                    break;
                }
                sprintf(endbuf, "%s %s\n", cp, name);
                cp = strtok(NULL, ",");
                endbuf = &endbuf[strlen(endbuf)];
                bsize = &localbuf[sizeof (localbuf)] - endbuf;
            }
            resp->valdat.dptr = localbuf;
            resp->valdat.dsize = strlen(localbuf);
        }

        free(buf);
        /* remove trailing newline */
        if (resp->valdat.dsize &&
            resp->valdat.dptr[resp->valdat.dsize-1] == '\n') {
            resp->valdat.dptr[resp->valdat.dsize-1] = '\0';
            resp->valdat.dsize -= 1;
        }

        resp->status = YP_TRUE;
        return (1);
    }
    nbuf = svc_getrpccaller(xprt);
    /*
     * OK, now I have a netbuf structure which I'm supposed to
     * treat as opaque...  I hate transport independance!
     * So, we're just gonna doit wrong...  By wrong I mean that
     * we assume that the buf part of the netbuf structure is going
     * to be a sockaddr_in.  We'll then check the assumed family
     * member and hope that we find AF_INET in there...  if not
     * then we can't continue.
     */
    if (((struct sockaddr_in *)(nbuf->buf))->sin_family != AF_INET)
        return (0);

    call_addr = ((struct sockaddr_in *)(nbuf->buf))->sin_addr.s_addr;

    cp = resp->valdat.dptr;
    if ((bp = strtok(cp, " \t")) == NULL) /* no address field */
        return (0);
    if ((cp = strtok(NULL, "")) == NULL)  /* no host field */
        return (0);
    bp = strtok(bp, ",");

    bestaddr = inet_addr(bp);
    while (cp = strtok(NULL, ",")) {
        ulong_t taddr;

        taddr = inet_addr(cp);
        if (ntohl(call_addr ^ taddr) < ntohl(call_addr ^ bestaddr))
            bestaddr = taddr;
    }
    cp = resp->valdat.dptr;
    sprintf(cp, "%s %s", inet_ntoa(*(struct in_addr *)&bestaddr), name);
    resp->valdat.dsize = strlen(cp);

    resp->status = YP_TRUE;

    return (1);
}

/* V1 dispatch routines */
void
ypoldmatch(SVCXPRT *transp, struct svc_req *rqstp)
{
    bool dbmop_ok = TRUE;
    struct yprequest req;
    struct ypreq_key nrq;
    struct ypresponse resp;
    char *fun = "ypoldmatch";
    DBM *fdb;

    memset((void *) &req, 0, sizeof (req));
    memset((void *) &resp, 0, sizeof (resp));

    if (!svc_getargs(transp,
                (xdrproc_t)_xdr_yprequest,
                (caddr_t)&req)) {
        svcerr_decode(transp);
        return;
    }

    if (req.yp_reqtype != YPMATCH_REQTYPE) {
        resp.ypmatch_resp_status = (unsigned)YP_BADARGS;
        dbmop_ok = FALSE;
    }

    if (dbmop_ok &&
        (((fdb = ypset_current_map(req.ypmatch_req_map,
                        req.ypmatch_req_domain,
                        &resp.ypmatch_resp_status))
                        != NULL) &&
                        yp_map_access(transp,
                        &resp.ypmatch_resp_status,
                        fdb))) {

        /* Check with the DBM database */
        resp.ypmatch_resp_valdat = dbm_fetch(fdb,
                        req.ypmatch_req_keydat);

        if (resp.ypmatch_resp_valptr != NULL) {
            resp.ypmatch_resp_status = YP_TRUE;
            if (!silent)
                printf("%s: dbm: %s\n",
                    fun, resp.ypmatch_resp_valptr);
            goto send_oldreply;
        }

        /*
         * If we're being asked to match YP_SECURE or YP_INTERDOMAIN
         * and we haven't found it in the dbm file, then we don't
         * really want to waste any more time.  Specifically, we don't
         * want to ask DNS
         */
        if (req.ypmatch_req_keysize == 0 ||
            req.ypmatch_req_keyptr == NULL ||
            req.ypmatch_req_keyptr[0] == '\0' ||
            strncmp(req.ypmatch_req_keyptr, "YP_SECURE", 9) == 0 ||
            strncmp(req.ypmatch_req_keyptr, "YP_INTERDOMAIN", 14) == 0)

            goto send_oldreply;

        /* Let's try the YP_MULTI_ hack... */
#ifdef MINUS_C_OPTION
        if (multiflag == TRUE && omultihomed(req, &resp, transp, fdb))
            goto send_oldreply;
#else
        if (omultihomed(req, &resp, transp, fdb))
            goto send_oldreply;
#endif

        /* Let's try DNS */
        if (!dnsforward) {
            USE_YP_INTERDOMAIN
            datum idkey, idval;
            idkey.dptr = yp_interdomain;
            idkey.dsize = yp_interdomain_sz;
            idval = dbm_fetch(fdb, idkey);
            if (idval.dptr)
                dnsforward = TRUE;
        }

        if (dnsforward) {
            if (!resolv_pid)
            setup_resolv(&dnsforward, &resolv_pid, &resolv_client,
                    resolv_tp, 0);

            if (req.yp_reqtype == YPREQ_KEY) {
            nrq = req.yp_reqbody.yp_req_keytype;

            resolv_req(&dnsforward, &resolv_client, &resolv_pid,
                    resolv_tp, rqstp->rq_xprt,
                    &nrq, nrq.map);
            }
            return;
        }
    }

    send_oldreply:

    if (!svc_sendreply(transp,
                (xdrproc_t)_xdr_ypresponse,
                (caddr_t)&resp)) {
        RESPOND_ERR;
    }

    if (!svc_freeargs(transp,
                (xdrproc_t)_xdr_yprequest,
                (char *)&req)) {
        FREE_ERR;
    }
}

void
ypoldfirst(SVCXPRT *transp)
{
    bool dbmop_ok = TRUE;
    struct yprequest req;
    struct ypresponse resp;
    char *fun = "ypoldfirst";
    DBM *fdb;

    memset((void *) &req, 0, sizeof (req));
    memset((void *) &resp, 0, sizeof (resp));

    if (!svc_getargs(transp,
                (xdrproc_t)_xdr_yprequest,
                (caddr_t)&req)) {
        svcerr_decode(transp);
        return;
    }

    if (req.yp_reqtype != YPFIRST_REQTYPE) {
        resp.ypfirst_resp_status = (unsigned)YP_BADARGS;
        dbmop_ok = FALSE;
    }

    if (dbmop_ok &&
        ((fdb = ypset_current_map(req.ypfirst_req_map,
                        req.ypfirst_req_domain,
                        &resp.ypfirst_resp_status))
                        != NULL) &&
                        yp_map_access(transp,
                        &resp.ypfirst_resp_status,
                        fdb)) {

        resp.ypfirst_resp_keydat = dbm_firstkey(fdb);

        if (resp.ypfirst_resp_keyptr != NULL) {
            resp.ypfirst_resp_valdat =
                dbm_fetch(fdb, resp.ypfirst_resp_keydat);

            if (resp.ypfirst_resp_valptr != NULL) {
                resp.ypfirst_resp_status = YP_TRUE;
            } else {
                resp.ypfirst_resp_status = (unsigned)YP_BADDB;
            }
        } else {
            resp.ypfirst_resp_status = (unsigned)YP_NOKEY;
        }
    }

    resp.yp_resptype = YPFIRST_RESPTYPE;

    if (!svc_sendreply(transp,
                (xdrproc_t)_xdr_ypresponse,
                (caddr_t)&resp)) {
        RESPOND_ERR;
    }

    if (!svc_freeargs(transp,
                (xdrproc_t)_xdr_yprequest,
                (caddr_t)&req)) {
        FREE_ERR;
    }
}

void
ypoldnext(SVCXPRT *transp)
{
    bool dbmop_ok = TRUE;
    struct yprequest req;
    struct ypresponse resp;
    char *fun = "ypoldnext";
    DBM *fdb;

    memset((void *) &req, 0, sizeof (req));
    memset((void *) &resp, 0, sizeof (resp));

    if (!svc_getargs(transp,
                (xdrproc_t)_xdr_yprequest,
                (caddr_t)&req)) {
        svcerr_decode(transp);
        return;
    }

    if (req.yp_reqtype != YPNEXT_REQTYPE) {
        resp.ypnext_resp_status = (unsigned)YP_BADARGS;
        dbmop_ok = FALSE;
    }

    if (dbmop_ok &&
        ((fdb = ypset_current_map(req.ypnext_req_map,
                    req.ypnext_req_domain,
                    &resp.ypnext_resp_status)) != NULL &&
        yp_map_access(transp, &resp.ypnext_resp_status, fdb))) {

        resp.ypnext_resp_keydat = dbm_nextkey(fdb);

        if (resp.ypnext_resp_keyptr != NULL) {
            resp.ypnext_resp_valdat =
            dbm_fetch(fdb, resp.ypnext_resp_keydat);

            if (resp.ypnext_resp_valptr != NULL) {
                resp.ypnext_resp_status = YP_TRUE;
            } else {
                resp.ypnext_resp_status = (unsigned)YP_BADDB;
            }
        } else {
            resp.ypnext_resp_status = (unsigned)YP_NOMORE;
        }
    }

    resp.yp_resptype = YPNEXT_RESPTYPE;

    if (!svc_sendreply(transp,
                (xdrproc_t)_xdr_ypresponse,
                (caddr_t)&resp)) {
        RESPOND_ERR;
    }

    if (!svc_freeargs(transp,
                (xdrproc_t)_xdr_yprequest,
                (caddr_t)&req)) {
        FREE_ERR;
    }
}

/*
 * This retrieves the order number and master peer name from the map.
 * The conditions for the various message fields are: domain is filled
 * in iff the domain exists.  map is filled in iff the map exists.
 * order number is filled in iff it's in the map.  owner is filled in
 * iff the master peer is in the map.
 */
void
ypoldpoll(SVCXPRT *transp)
{
    struct yprequest req;
    struct ypresponse resp;
    char *map = "";
    char *domain = "";
    char *owner = "";
    uint_t error;
    char *fun = "ypoldpoll";
    DBM *fdb;

    memset((void *) &req, 0, sizeof (req));
    memset((void *) &resp, 0, sizeof (resp));

    if (!svc_getargs(transp,
                (xdrproc_t)_xdr_yprequest,
                (caddr_t)&req)) {
        svcerr_decode(transp);
        return;
    }

    if (req.yp_reqtype == YPPOLL_REQTYPE) {
        if (strcmp(req.yppoll_req_domain, "yp_private") == 0 ||
            strcmp(req.yppoll_req_map, "ypdomains") == 0 ||
            strcmp(req.yppoll_req_map, "ypmaps") == 0) {

            /*
             * Backward comatibility for 2.0 NIS servers
             */
            domain = req.yppoll_req_domain;
            map = req.yppoll_req_map;
        } else if ((fdb = ypset_current_map(req.yppoll_req_map,
                req.yppoll_req_domain,
                &error)) != NULL) {
            domain = req.yppoll_req_domain;
            map = req.yppoll_req_map;
            ypget_map_order(map, domain,
                    &resp.yppoll_resp_ordernum);
            ypget_map_master(&owner, fdb);
        } else {
            switch ((int)error) {
            case YP_BADDB:
                map = req.yppoll_req_map;
                /* Fall through to set the domain too. */

            case YP_NOMAP:
                domain = req.yppoll_req_domain;
                break;
            }
        }
    }

    resp.yp_resptype = YPPOLL_RESPTYPE;
    resp.yppoll_resp_domain = domain;
    resp.yppoll_resp_map = map;
    resp.yppoll_resp_owner = owner;

    if (!svc_sendreply(transp,
                (xdrproc_t)_xdr_ypresponse,
                (caddr_t)&resp)) {
        RESPOND_ERR;
    }

    if (!svc_freeargs(transp,
                (xdrproc_t)_xdr_yprequest,
                (caddr_t)&req)) {
        FREE_ERR;
    }
}

void
ypoldpush(SVCXPRT *transp)
{
    struct yprequest req;
    struct ypresp_val resp;
    pid_t pid = -1;
    char *fun = "ypoldpush";
    DBM *fdb;

    memset((void *) &req, 0, sizeof (req));

    if (!svc_getargs(transp,
                (xdrproc_t)_xdr_yprequest,
                (caddr_t)&req)) {
        svcerr_decode(transp);
        return;
    }

    if (((fdb = ypset_current_map(req.yppush_req_map,
                    req.yppush_req_domain,
                    &resp.status)) != NULL) &&
        (yp_map_access(transp, &resp.status, fdb))) {

        pid = vfork();
    }

    if (pid == -1) {
        FORK_ERR;
    } else if (pid == 0) {
        ypclr_current_map();

        if (execl(yppush_proc, "yppush", "-d", req.yppush_req_domain,
                req.yppush_req_map, NULL)) {
            EXEC_ERR;
        }
        _exit(1);
    }

    if (!svc_sendreply(transp,
                (xdrproc_t)xdr_void,
                (caddr_t)NULL)) {
        RESPOND_ERR;
    }

    if (!svc_freeargs(transp,
                (xdrproc_t)_xdr_yprequest,
                (caddr_t)&req)) {
        FREE_ERR;
    }
}

void
ypoldpull(SVCXPRT *transp)
{
    struct yprequest req;
    struct ypresp_val resp;
    pid_t pid = -1;
    char *fun = "ypoldpull";
    DBM *fdb;

    memset((void *) &req, 0, sizeof (req));

    if (!svc_getargs(transp,
                (xdrproc_t)_xdr_yprequest,
                (caddr_t)&req)) {
        svcerr_decode(transp);
        return;
    }

    if (req.yp_reqtype == YPPULL_REQTYPE) {

        if (((fdb = ypset_current_map(req.yppull_req_map,
                        req.yppull_req_domain,
                        &resp.status)) == NULL) ||
            (yp_map_access(transp, &resp.status, fdb))) {
            pid = vfork();
        }

        if (pid == -1) {
            FORK_ERR;
        } else if (pid == 0) {
            ypclr_current_map();

            if (execl(ypxfr_proc, "ypxfr", "-d",
                    req.yppull_req_domain,
                    req.yppull_req_map, NULL)) {
                EXEC_ERR;
            }
            _exit(1);
        }
    }

    if (!svc_freeargs(transp,
                (xdrproc_t)_xdr_yprequest,
                (caddr_t)&req)) {
        FREE_ERR;
    }
}

void
ypoldget(SVCXPRT *transp)
{
    struct yprequest req;
    struct ypresp_val resp;
    pid_t pid = -1;
    char *fun = "ypoldget";
    DBM *fdb;

    memset((void *) &req, 0, sizeof (req));

    if (!svc_getargs(transp,
                (xdrproc_t)_xdr_yprequest,
                (caddr_t)&req)) {
        svcerr_decode(transp);
        return;
    }

    if (!svc_sendreply(transp, xdr_void, 0)) {
        RESPOND_ERR;
    }

    if (req.yp_reqtype == YPGET_REQTYPE) {

        if (((fdb = ypset_current_map(req.ypget_req_map,
                        req.ypget_req_domain,
                        &resp.status)) == NULL) ||
            (yp_map_access(transp, &resp.status, fdb))) {

            pid = vfork();
        }

        if (pid == -1) {
            FORK_ERR;
        } else if (pid == 0) {

            ypclr_current_map();

            if (execl(ypxfr_proc, "ypxfr", "-d",
                    req.ypget_req_domain, "-h",
                    req.ypget_req_owner,
                    req.ypget_req_map, NULL)) {

                EXEC_ERR;
            }
            _exit(1);
        }
    }

    if (!svc_freeargs(transp,
                (xdrproc_t)_xdr_yprequest,
                (caddr_t)&req)) {
        RESPOND_ERR;
    }
}

static int
omultihomed(struct yprequest req,
        struct ypresponse *resp, SVCXPRT *xprt, DBM *fdb)
{
    char *cp, *bp;
    char name[PATH_MAX];
    struct netbuf *nbuf;
    ulong_t bestaddr, call_addr;

    if (strcmp(req.ypmatch_req_map, "hosts.byname"))
        return (0);

    if (strncmp(req.ypmatch_req_keyptr, "YP_MULTI_", 9)) {
        datum tmpname;

        strncpy(name, "YP_MULTI_", 9);
        strncpy(name + 9, req.ypmatch_req_keyptr,
            req.ypmatch_req_keysize);
        tmpname.dsize = req.ypmatch_req_keysize + 9;
        tmpname.dptr = name;
        resp->ypmatch_resp_valdat = dbm_fetch(fdb, tmpname);
    } else {
        resp->ypmatch_resp_valdat =
            dbm_fetch(fdb, req.ypmatch_req_keydat);
        if (resp->ypmatch_resp_valptr != NULL)
            return (1);
    }

    if (resp->ypmatch_resp_valptr == NULL)
        return (0);

    strncpy(name, req.ypmatch_req_keyptr, req.ypmatch_req_keysize);
    name[req.ypmatch_req_keysize] = NULL;

    nbuf = svc_getrpccaller(xprt);

    /*
     * OK, now I have a netbuf structure which I'm supposed to treat
     * as opaque...  I hate transport independance!  So, we're just
     * gonna doit wrong...  By wrong I mean that we assume that the
     * buf part of the netbuf structure is going to be a sockaddr_in.
     * We'll then check the assumed family member and hope that we
     * find AF_INET in there...  if not then we can't continue.
     */
    if (((struct sockaddr_in *)(nbuf->buf))->sin_family != AF_INET)
        return (0);

    call_addr = ((struct sockaddr_in *)(nbuf->buf))->sin_addr.s_addr;

    cp = resp->ypmatch_resp_valptr;
    if ((bp = strtok(cp, "\t")) == NULL)    /* No address field */
        return (0);
    if ((cp = strtok(NULL, "")) == NULL)    /* No host field */
        return (0);
    bp = strtok(bp, ",");

    bestaddr = inet_addr(bp);
    while (cp = strtok(NULL, ",")) {
        ulong_t taddr;

        taddr = inet_addr(cp);
        if (ntohl(call_addr ^ taddr) < ntohl(call_addr ^ bestaddr))
            bestaddr = taddr;
    }

    cp = resp->ypmatch_resp_valptr;
    sprintf(cp, "%s %s", inet_ntoa(*(struct in_addr *)&bestaddr), name);
    resp->ypmatch_resp_valsize = strlen(cp);

    resp->ypmatch_resp_status = YP_TRUE;

    return (1);
}